1. Field of the Invention
The present invention relates to an ultrasonic piezoelectric revolving resonator in which a piezoelectric deformation is revolved under the first order resonating mode where a gravitational center of a piezoelectric disk, annulus or cylinder, or cylindrical pipe is revolved and an ultrasonic motor using the piezoelectric revolving resonator, and more particularly to the improvement of an excitation mechanism therefor.
2. Prior Art Discussion
In a conventional piezoelectric revolving resonator and a motor using the resonator, in particular in an ultrasonic revolving resonator (Japanese Patent Application No. 62-11373 (Laid-Open No. 63-181676(A)) and a gravity revolving type ultrasonic motor (Japanese Patent Application No. 52-11374 (Laid-Open No. 63-181677(A))), both proposed by one of the present inventors, it is necessary to drive the components by using an electric source having two or more outputs different in phase. Also, for instance in a four-polar quadrapole piezoelectric revolving resonator disclosed in Japanese Patent Application 62-11375 (Laid-Open No. 63-181678(A)), entitled "FOUR-POLAR ULTRASONIC REVOLVING RESONATOR", four regions divided over a disc, annulus or cylinder, or cylindrical pipe along a circumference thereof have to be driven by four phase voltages different in phase by .pi./2.
Accordingly, in such an arrangement the drive circuit is complicated and the number of wirings is increased. Therefore it was difficult to reduce the electric source in size and to decrease the cost. These disadvantages could be eliminated by simplifying the four-phase drive to a two-phase drive in accordance with a method for polarizing the adjacent regions of the four regions in opposite polarities. However, in comparison with the single phase drive, this was complicated, and it was difficult to manufacture the piezoelectric revolving resonator in which the torques of the adjacent poles were balanced.